Lukaku's departure could be the least of Everton's worries this summer.Getty Images

Despite reaching two domestic cup semi-finals only to be knocked out by the Manchester clubs, Everton rivalled Aston Villa, Chelsea and Newcastle United for the worst domestic campaign in the top flight last term after dramatically failing to meet expectations.

An 11th place finish and the regressing of several of the club's young players was enough to see Roberto Martinez disposed of one game before the end of the campaign.

At the time of writing, The Toffees are yet to appoint a successor to the Spaniard but with several of their leading lights set to be on the way out of Merseyside, you can understand why the post remains unfilled. Farhad Moshiri's arrival is expected to be accompanied by investment in the transfer window, but that will inevitably be to replace the star players destined to depart.

Business so far

Before any transfer business can begin, the club must solve the managerial situation – and quickly before obtainable targets become snapped up. The names linked with a move include former boss David Moyes, ex-Ajax coach Frank de Boer and Manuel Pellegrini after his exit from Manchester City. Ronald Koeman and Unai Emery, of Southampton and Sevilla respectively, are expected to be out of reach.

What they need

The central theme for much of Everton's 2015-16 season was not how wafer-thin options denied them of a greater rewards, but that many players failed to fulfil their potential. A manager who can harness the talent at his disposal is badly required. As far as players in the window are required, a new goalkeeper to replace the scatty Joel Robles, another experienced figure to play alongside John Stones and a midfielder with some much-needed guile will top the list for the new man at the helm.

Moshiri is reportedly ready to invest heavily in Everton - but can he hold on their best players?Getty Images

Who could join

Naturally, without a manager directing the transfer traffic rumoured targets have been few and far between. With Pep Guardiola rumoured with signing a new goalkeeper upon his arrival at Manchester City, Joe Hart has been heavily linked with a move to Goodison. Saido Berahino appears to have missed out on a move to Tottenham, but Everton are interest in recruiting the West Bromwich Albion forward, while the out-of-contract Michael Carrick would shore up the midfield area.

Who could leave

Even before the exit of Martinez, the club's star turns were queuing up to leave for pastures new. While the new manager might be able to tempt a few to remain, Romelu Lukaku appears to have made his mind up over a move to either Chelsea, Bayern Munich or Manchester United in a deal worth £65m.

What the manager has said

Still to be appointed, naturally we have heard very little on Everton's transfer plans this summer, but if newspaper reports are any indicator then supporters can be encouraged despite the period of uncertainty. Prior to his arrival, The Mirror understood Iranian Moshiri was ready to invest £100m into the club purely for new players, and chairman Bill Kenwright notably highlighted his "financial wherewithal" as the key reason behind the partnership.